COMP: disable some compiler warnings

- The -Wno-deprecated-copy flag for gcc-9.2.0

  In the future we may indeed wish to explicitly request default
  generated constructors and assignment operators, but at the moment
  these are still acceptable.

- The -Wno-alloc-size-larger-than flag for mingw compilations

  Related to differences in PTRDIFF_MAX vs SIZE_MAX on the target.
  Several issues related to this can be found in the gcc bug reports
  and on stackoverflow etc.

wmake/rules/General/Gcc/c++

@@ -13,7 +13,7 @@ ptFLAGS     = -DNoRepository -ftemplate-depth-100
 c++WARN     = \
     -Wall -Wextra -Wold-style-cast \
     -Wnon-virtual-dtor -Wno-unused-parameter -Wno-invalid-offsetof \
-    -Wno-attributes -Wno-unknown-pragmas
+    -Wno-attributes -Wno-unknown-pragmas -Wno-deprecated-copy
 
 c++LESSWARN = \
     -Wno-old-style-cast -Wno-unused-local-typedefs -Wno-array-bounds \

wmake/rules/linux64Mingw/c++

@@ -9,7 +9,7 @@ include $(RULES)/c++$(WM_COMPILE_OPTION)
 
 c++FLAGS    = $(c++ARCH) $(GFLAGS) $(c++WARN) $(c++OPT) $(c++DBUG) $(ptFLAGS) $(LIB_HEADER_DIRS)
 
-Ctoo        = $(WM_SCHEDULER) $(CC) $(c++FLAGS) -c $< -o $@
+Ctoo        = $(WM_SCHEDULER) $(CC) $(c++FLAGS) -Wno-alloc-size-larger-than -c $< -o $@
 cxxtoo      = $(Ctoo)
 cctoo       = $(Ctoo)
 cpptoo      = $(Ctoo)